7. Ontology Engineering Ingeborg Ødegård Oftedal Overview ● Ontology → Concept of existence ● Information Science ○ hierarchical data structure with objects ○ rules within one domain ● Artificial Intelligence ○ knowledge management ○ natural language processing ○ e-commerce ○ education ○ semantic web Ontology Engineering ● Common vocabulary ● Information sharing ● Knowledge base ● Taxonomy ○ set of classes and objects and their relationship ● Data collection process Ontology Applications ● Categories of ontology applications ○ Neutral Authoring ○ Ontology as Specification ○ Common Access to Information ○ Ontology-based search Contructing Ontology ● Iterative approach ○ Set the scope ○ Evaluate reuse ○ Enumerate terms ○ Define taxonomy ○ Define properties ○ Define facets ○ Different facets on slots ○ Define instances ○ Check for anomalies Ontology Development Toops ● DAG-Edit ● Protege 2000 ● WonderTools ● WebOnto Spot ontology example Ontology Methods ● TOVE (TOronto Virtual Enterprise) ● Cyc Knowledge Base ● Electronic Dictionairy Research ● WordNet ● Methontology ● On-To-Knowledge Ontology Sharing And Merging ● Logic ○ Sharing information automatically with a common subset ● Ontology ○ Same object → different name, differen object → same name ● Computation ○ Same name and definitions → different behaviour Ontology Libraries ● DAML, Ontolingua Library, Protege Ontology Library ● Upper ontologies ○ IEEE Standard Upper Ontology ○ Cyc ● General ontologies ○ www.dmoz.org ○ WordNet ○ Domain-specific ontologies ○ UMLS Semantic Net ○ GO ○ Chemical Markup Language Ontology Matching ● String matching ● Comparing Ontologies Ontology Mapping ● Mapping between local ontologies ● Mapping between integrated global ontology and local ontologies ● Mapping for ontology merging, integration, or alignment Ontology Mapping Tools ● GLUE ● Learning Source Description ● OntoMorph Conclusion ● Basic issues for designing and building ontologies ● Requires more ontology engineering.